Sheet-glass apparatus



sept'. 22, 1925. w

- E. T. FERNGREN SHEET GLASS APPARATUS Filed Dec. 2e 1924 ATTRNEY heated and cooied te produce z:

` regular i ed to many of ih@ iol-ms of machines www m `und healing' Chm'nhoy i to pmifimij; sentiithm lhe Same ''m the g'mipi'ia-,cofi hvng drawn ihm a shack. rl'zmued above the Sourve of glass G are grrnupb hf hcuug' eiements S and 9 respectively und groups uf cooling elements l() :and l1 ICspcii The heaing esunts designated bg," th@ uumemls 8 muy be 'm the foi-h: mf gashlu'ners and @Je Contained in the shi@ 'vzxiis 'if he,

ux* nher #urinarie comici' wifi 11h50??? haas heat from the The efgfiing mation wii cause the hppa? surface iff le molten H" QS 6 to homme more plastic han this un gigas, and ai fh@ Same time ecuizu change, 7 n imm 'mi out. The

)n the construction Shown i Fig. L "che vertically ndjusiahh cfwhi Q5 52S pref@ bly mmpriscs :1, hox iik@ truer WTO. having HHS of a suitable mom?, in which disposed u phunliiy minimis j? thlnugh whin'h :my 'form 0'1" e'Tec'i/'Q Cowling; modmu may also be passed. ll'migmi hcl zfzii'h the und 0'1" the ulmu'e auf@ pixmiit); off immers :2S to assist in iweping thv, jmdm "i iiuiffi.

LIl

iff its smh-ce. 1

i S'Lchilled and withdrawn from the pot in sheet fifiii.A rotatable preferably vertically ad jjustable roll or drum 42,'which is air or y water cooled, is arranged at the sheet supy plyingmeniscusas is shown, and is prefer- "'10.,ably resilientlyv seated upon the upper surface to prevent buckling or other irregular i, movement of the surface skin as it is be ing. drawn from .the pot. rllhe ,sheet 29 is then deflected over the bending roll 43 as in -construction shown in Fig. 2.- The series of gasl flames 44 are played through series of ports formed in the hood 45, and

-'radiant heat is reflected upon the upper surface" of the sheet in its substantially vertisheet formation is exposed to radiant heat `energy from the glass body in the end 18 of the pot and the heat arising from the chamber 39.' y f The roll or drum 42 is of particular imlv.portance in the uniform conditioning of the glass at the point of lift of the sheet which yniakes lit possible to draw a very flat sheet. .y :I The roll 42 also determines by the speed l"1Q givenvthereto the quantity advance of the .supplying glass into the line of draw, so thatit isI now possible to considerably increase the speed of draw of any given vlthickness of sheet.

,In thedrawing the sheet from the forward end of the {ioating plastic unit at the point where the drum 42 contacts, this drum .or roll becomes a barrier against which the glass is raised by the drawing 'force and :i 5,0 sheet, as the supplementally heated more ,fluent glass which is picked up at the point of deliection and at the heated side of the vvrne'nivscusis lacking in rigid properties.

.This condition is largely responsible for M55, the ,absence of conflicting strain in the sheet vchiririg its formingr period.

` The peripheral speed given to the drum ,42Kwill largely determine the speed at which he quantity of glass forming the supply 601. ng source of the sheet is advanced, and

he speed at which this glass is drawn will mglcterininethe.thickness of the sheet.

' yThe "radiant heat released against the glass sheet body tends to soften it and re to which `it will adhere as it is surfacey tain enough pliancy therein to insure easy bending over the roll 43.

The particular similarity feature of all ofthe cooling means shown for treating' the surface of the sheet'supplying glass is this, that instead of the commonly used thinwalled water coolers which ordinarily chill a small portion of the surface of the glass very quickly, the coolers shown function l'ess drastically, and in a more mild manner over alarger area of the surface of the glass from which the heat is absorbed gradually.

Each of the several modes of coolers shown are box shaped,'and of a size to nearly till the chamber in which it is placed to thereby form a large negative temperature or cold zone into which the heat of the glass will be impelled. 'The lower surface of thev fiat metal plate which formsthe bottom of each cooler should preferably be located fairly close to the glass surface so as to exclude air currents from the space between it and the glass. This metal plate may be permitted to become heated up to a certain point, but i should normally have a temperature much below that of the adjacent glass surface.

The cooler 46 shown in` Fig. 3 is air cooled and may be formed of monel or other metal, as air cooling through almost any metal body imparts a uniform cooling effect to the surface of a pool of glass, copper being the best heat conductor but not exactly suitable to -employ without contact with water because of its low softening point.

In forming wide plate glass-the vparti#- cular initial and subsequent steps of this process of imparting an equally fixed pliancy to the glass which 1s going into the sheet, will be useful in preventing warping and waving of the sheet body.

The roll 42 may be rotated in the direction of draw at a speed much below the drawing speed whenv a single strength sheetA is being drawn, but in any' case the roll 42 will largely fix or impress the same speed on the glass entering-the base of the sheet.

The cooling of the glass by the roll 42 may be more or less according to the degree of internal or external cooling given tothe roll and the cooling medium used.

ln carrying out the process under the conditions shown in Fig. 1,'the sheet 22 is lifted or raised over the upper edge of the member 21, the tautness and tenacious structure of the' top stratum 45 of the glass enabling this procedure. u

The iop layers 47 formed under the iniuence of cooler 26 is normally-more yielding and stretchable at its forward end, and also more firmly attached to the supplyingr glass body 6, so that while progressively yielding the sheet the resistance to the drawing force is great enough to prevent a speedy unit ,Matanzas until a uniform homogeneous skin is formed,

y and continuously removingthe plastic surface skin as a sheet of glass from the molten body.

` a body of moiten glass therein ytively and successively heating -and then producing a sheet of glass from the 7. The rprocess sively causing `plastic glass upon of'producing sheet glass which consists inY 'solid sheet of glass within the environs oi the'melting tank and upon thesurface or'.

and cooling,

for producing sheet glass by alternateheating and cooling, and

glass,

means for drawing oi the sheet of plastic glassI in sheet form. 9. In an apparatus the surface of' the pool of molten glass,

,means for-.cooling the same,

said heating and cooling means being arranged in relation that the surface of the. moltenglass Will be alternatelyv heated and cooled to form a ksemi-solid skin lon the surface of the pool, and means for removing this skin from the pool in sheet form.

10. ln .an apparatus for producing sheet glass, in combination of means for successively and alternately heating and cooling n the surface of the pool of molten glass to the formation of a semiby alternafor producing sheetA in combination of means for heating p form a semi-solid skin, and means for drawing theskin from the pool in sheet form and in a horizontal plane.

11. In an apparatus for producing sheet glass, in combination of means tor successively and alternately heating and cooling the surface of a pool of molten glass to cree ate a skin, means to withdraw the skin from the pool in sheet form, and means for lire polishing the sheet as it leaves the pool.

w 12.3111 sheet glass apparatus, in combina tion di' means for successively and alternately heating and cooling the surface oi' a pool of molten glass to form a semi-solid. skin,yand means to lift the skin and draw it oit in sheet form.

13. ln sheet glass apparatus, in combina tion of means for successively and alternately heating and cooling the surface of a pool of molten glass to form a skin, and means for mechanically advancing the skin to the oint of draw Where it is drawn away in sheet form.

14;. in sheet glass apparatus, in combination ontl means for forming a semi-solid layer on a source of molten glass, means tor mechanically advancing the layer to the point of draw, and means to litt the skin and draw it oiA in sheet form.

Sioned at roledo, in the county of Lucas, and tate of Ohio, this Q/lth day of Decem ber, 1924.

` nnocn fr. aanneemt. 

